Rae announced his departure from Leeds, where he had spent the previous two years.
And the Scottish goalkeeper shared a picture of himself in Blackburn training gear on Instagram last month.
But in a cryptic update posted earlier today, Rae wrote: 'Leeds soon'.
Leeds have also taken an unnamed goalkeeper on trial for the game at Ings Lane, with Bailey Peacock-Farrell understood to be injured and both Kiko Casilla and Kamil Miazek with the Whites' squad currently touring Australia.
Whether or not Rae could return to Leeds on a full-time basis remains to be seen, although a move to Blackburn now looks unlikely.
And it would appear that, for now at least, the teenager is simply there to make up the numbers.
First-team players Ben White, Ezgjan Alioski, Mateusz Klich, Jack Clarke and Helder Costa are all named in Leeds' starting XI to face the non-league side.
Have something to tell us about this article?